If you're a dedicated San Diego playgoer, this just might be a good month to consider taking a stage-cation, because seeing all these shows likely is going to amount to a full-time pursuit.

Besides productions that have opened recently (including Intrepid Shakespeare Co.'s musical "Midsummer Night's Dream," now in previews, and Ion's "The Mystery Plays"), plus such long-runners as the Old Globe Shakespeare Festival and "miXtape" (plus "See How They Run") at Lamb's, here's a roundup of what's coming up this month:

• “The Underpants,” North Coast Rep, Sept. 5-30: Mark Pinter directs the season-opening San Diego premiere of Steve Martin's comedy about an upstanding man who is scandalized when his wife’s intimate garments fall down in public.

• “W.C. Fields By Himself,” Sept. 5-30: Playwright-actor-producer Dale Morris is the title comedian in this show, which he’s been developing for years. The piece, which looks back on the life of the fabled (and troubled) icon, goes up at the Tenth Avenue Theatre downtown.

• "Allegiance - A New American Musical," Old Globe, Sept. 7 to Oct. 21: The theater opens its 2012-13 winter season with the world-premiere musical about the internment of Japanese-Americans during World War II. The show stars Tony Award-winner Lea Salonga (“Miss Saigon”), Broadway veteran and "Glee" star Telly Leung and "Star Trek" icon George Takei.

Takei, whose own family was interned, has been a prime inspiration for and force behind "Allegiance." Stafford Arima (“Altar Boyz”) directs the piece, written by Jay Kuo, Lorenzo Thione and Marc Acito, with a score by Kuo.

• “Pippin,” Diversionary Theatre, Sept. 7 to Oct. 14: James Vasquez directs this revival of the early musical by Stephen Schwartz (of “Godspell” and “Wicked” fame). It's a kind of contemporary fairy tale centered on the story of a young prince. Diversionary's cast includes such local favorites as Courtney Corey and Tony Houck.

• “Same Time, Next Year,” Sept. 7 to Oct. 7, New Village Arts Theatre: The romantic comedy, which replaced “Next to Normal” on the NVA schedule, stars real-life married couple Manny and Melissa Fernandes.

• "Perfect Wedding," Scripps Ranch Theatre, Sept. 7 to Oct. 7: SRT opens its 34th (!) season with a staging of Robin Hawdon's comedy; it's the second show to be directed there by Jessica John, a wide-ranging San Diego actor.

• “Welcome to Ramallah,” Sept. 7-30: The local publication ArtsNFashion Magazine is producing this staging of the Mideast-set drama by Sonja Linden and Adah Kay. George Bailey and Paola Hornbuckle direct the show at Swedenborg Hall in University Heights.

• “Sweeney Todd: The Demon Barber of Fleet Street,” Moonlight Stage Productions, Sept. 19 to Oct. 6: Moonlight puts up its last show of the summer season - and the last of Kathy Brombacher's three-decade tenure as artistic director. Steven Glaudini, who was just named Brombacher's successor, directs Stephen Sondheim's darkly comic musical about revenge, redemption and mystery-meat pies.

• “Mistakes Were Made,” Cygnet Theatre, Sept. 20 to Oct. 21: The versatile comic actor Phil Johnson stars in the West Coast premiere of Craig Wright's play about a struggling theater producer who takes on an impossibly epic project. Shana Wride directs.

• “Sam Bendrix at the Bon Soir,” La Jolla Playhouse, Sept. 24 to Oct. 10: Keith Bunin's play is the latest production in the Playhouse’s site-specific “Without Walls” series. Luke Macfarlane stars in the piece, directed by Mark Rucker at Martini’s Above Fourth in Hillcrest. The show, which features songs by Cole Porter, Kurt Weill and George Gershwin, unfolds in a 1950s Greenwich Village nightclub.

• “Kita y Fernanda,” Mo`olelo Performing Arts Co., Sept. 27 to Oct. 21: Seema Sueko and Robert Castro codirect Tanya Saracho’s play about two Mexican girls who grow up in the same Texas household, but under starkly different circumstances.

• "Footloose," San Diego Musical Theatre, Sept. 28 - Oct. 14, 2012: SDMT returns to the Birch North Park Theatre for the third show of its season with this movie-based musical about a culture clash in a small town. Robert Marra directs.

• “Good People,” Old Globe Theatre, Sept. 29 to Oct. 28: Paul Mullins directs the play by Pulitzer-winner David Lindsay-Abaire (“Rabbit Hole”) about the fallout from an old romance amid hard times in Boston. Last year's Broadway run earned two Tony nominations.

• “Exit Interview,” San Diego Rep, Sept. 29 to Oct. 21: The Rep presents a "rolling world premiere" of William Missouri Downs’ satire about a professor who has just been downsized. The show, directed by Rep artistic chief Sam Woodhouse, stars Herbert Siguenza, the Culture Clash co-founder whose 18-month residency is supported with a New Generations Future Leaders grant.